1. Field of the Invention
The present invention relates to a video scope system comprising an optical system disposed in a distal end of an insertion section to be inserted in an object under inspection for forming an image of the object, a solid state image sensor such as CCD, BBD, SIT and the like for picking up the image of the object, a video processor unit for processing an image signal supplied from the solid state image sensor, and a monitor for receiving the image signal to display the image of an inner portion of the object under inspection.
2. Description of the Related Art
Various types of video scope systems are already known: U.S. Patent specification No. 4,539,586, for example, discloses a video scope system as shown in FIG. 1. A video scope 1 of this video scope system has an insertion section 1a which is inserted in the object under inspection, and a handle section 1b connected to a proximal end of the insertion section 1a. An image sensor (not shown) is disposed in a distal end of the insertion section 1a, in which there are provided a light guide feeding a light for illuminating a subject under inspection, i.e., an inner wall of a cavity of a human body, an air supply tube for supplying air into the object under inspection, a water supply tube for supplying water for removing foreign matters applied on an objective lens, an inert gas tube for feeding an inert gas into the object under inspection, and a conductor bundle for supplying a driving signal to the image sensor and feeding an image signal supplied from the image sensor to a point outside the video scope 1. These light guide, air supply tube, water supply tube, gas tube, and conductor bundle are arranged in a universal cable 2 connected to the handle section 1b, and are connected to an external apparatus 4 through a connector 3. A light source unit feeding an illuminating light into the light guide, an air supply pump, and a video processor unit are arranged and housed in the external apparatus 4. The image signal supplied from the image sensor is supplied to the video processor unit of the external apparatus 4 through a lead extending through the insertion section 1a and the universal cable 2, is processed by the video processor unit in a usual manner, and then is supplied to a monitor 5 so that an image of an inner portion of the object under inspection can be displayed.
U.S. Patent specification No. 4,601,284 discloses a video scope system constructed in such a manner that an attachment including a solid stage image sensor is detachably attached to an eyepiece section provided at a handle section of a usual optical fiber scope having a light guide and an image guide, so that an endoscope image is displayed on a monitor. In this conventional system, a connector connected to a universal cord cable which is connected to the handle section, and a connector connected to a conductor bundle which is connected to an adapter, are respectively connected to sockets provided on an external apparatus housing a light source unit and a video processor unit.
In the conventional video scope system described above, since the video processor unit, the light source unit, the air supply pump and the like are all disposed in the external apparatus, heat generated by a light source lamp provided in the light source unit interferes with the proper functioning of electronic circuits provided in the video processor unit.
If a motor driving a stop for carrying out an automatic gain control for the light source unit, a motor for inserting an emergency lamp into an optical path, or a motor for rotating a color filter in the optical path in a field or frame sequential television system are provided in a housing together with the electronic circuits, the heat generated by these motors is likely to have an adverse influence on the electronic circuits, and noise generated by these motors also may affect the operation of the electronic circuits.
Further, if a part of the external apparatus malfunctions or is damaged, the external apparatus must be replaced, as a complete unit, for a new unit. Therefore, the conventional system has a drawback in that the running costs are increased, and since the operation for replacing the video processor unit is complicated and time-consuming, if the change-over of the unit must be made during the inspection of the inside portion of a patient body, the patient is subjected to unnecessary pain and anxiety, because the change-over operation cannot be made promptly.
In U.S. Patent Specification No. 4,539,586, the electrical connection, optical connection, and mechanical connection are all made through one connector 3, and thus the connector has a complicated construction and is very costly. Also, the connector must be carefully connected to and disconnected from a socket to ensure a good connection between the connector and the socket and to prevent damage thereto, and accordingly, the operation becomes complicated.
The above described problems occur not only in the video scope in which the image sensor is disposed in the distal end of the insertion section thereof, but also in a video scope system in which an image transmitted by the image guide is picked up by an image sensor disposed in a proximal end of the insertion section.